Responses of Queensland fruit fly females to fruit odours are studied

Plant & Food Research scientists, as part of the Better Border Biosecurity (B3) research collaboration, and collaborators at the Institut Agronomique néo-Calédonien, have been collecting and analysing the odours of four ripe fruit hosts in a project aimed at developing a female attractant for Queensland fruit fly surveillance.

The work is the subject of a post on Plant & Food Research’s website.

Females of the Queensland fruit fly (QFF), Bactrocera tryoni, are among the most damaging pests of horticulture in the South Pacific. New Zealand is at high risk of incursions and deploys a national surveillance system for early detection, to enable a fast eradication response.

Current detection relies on a parapheromone lure for males of the species. But no long- lasting attractants for female QFF exist, which excludes the half of the population which causes the most damage.

In their research aimed at developing a female attractant for surveillance, the collaborating scientists from Plant & Food Research and the Institut Agronomique néo-Calédonien collected and analysed the odours of four ripe fruit hosts (known and potential) – orange, cherry guava, banana, and feijoa.

Using gas-chromatography coupled with electro-antennographic detection (EAD), the researchers detected 41 compounds that stimulated a response in the female fruit fly, seven of which were found to be common for more than one fruit.

Overall, mated females responded more often and with higher intensity than virgin females, as expected when mated females search for fruit to oviposit (lay eggs).

The 26 compounds that triggered the largest and most frequent responses in female QFF, were tested in an olfactometer – a device designed to analyse the behavioural response of live insects to an odour stimulus. In contrast to the EAD measurement, behavioural responses did not show strong differences between mated and virgin females, although they did differ significantly between the compounds.

No correlation was detected between the electrophysiological and behavioural responses.

Field testing with the behaviourally active compounds is being carried out in Australia, for the development of a lure for female Queensland fruit fly.

This work was performed with the support of a Pacific Fund from the Foreign Ministry of France. This project was funded by Horticulture Innovation Australia Limited with co-investment from The New Zealand Institute for Plant and Food Research Limited and support from the Better Border Biosecurity collaboration (b3nz.org.nz).

Journal Reference
Mas F, Manning L, Singlet M, Butler R, Mille C, Suckling DM 2020 Electrophysiological and Behavioural Responses of Queensland Fruit Fly Females to Fruit Odors J Chem Ecol 46 (2) https://doi.org/10.1007/s10886-019-01143-8

Source:  Plant & Food Research

Biosecurity NZ reports successful end to fruit fly operation in Auckland

Biosecurity New Zealand has ended its Northcote fruit fly operations and lifted restrictions on the movement of fruit and vegetables on Auckland’s North Shore.

The move signals the end of an almost year-long operation, including a massive effort by the community, triggered by the discovery of a Queensland fruit fly in a surveillance trap in the area last February.

“While this is great news, we remind people in the area to still stay vigilant for signs of the fruit fly,” says Biosecurity New Zealand spokesperson Dr Cath Duthie.

“It’s now been 6 months since a fly was last trapped in the area, and this, along with an intensive baiting programme throughout the spring and the inspection of hundreds of kilos of fruit without a find, has given us confidence there is currently no breeding population of the Queensland fruit fly in Northcote.

“We can once again declare that New Zealand is free of the Queensland fruit fly,” Dr Duthie says. Continue reading

Fruit fly in Auckland – Controls are reintroduced after another male is found

Biosecurity New Zealand has reintroduced controls on the movement of fruit and vegetables in the Auckland suburb of Northcote following the detection of a further Queensland fruit fly.

A single male fruit fly has been found in one of an enhanced network of traps which remained in place following the discovery of six other fruit flies in the area between 20 February and 14 March.

The previous restrictions on the movement of fruit and vegetables were lifted earlier this month, although additional surveillance was kept in place as a precautionary measure.

The latest fly was found 185 metres from the edge of the previous Control Zone A, and 460 metres away from where a cluster of male flies was found, says Biosecurity New Zealand spokeswoman Dr Catherine Duthie. Continue reading

Second Queensland fruit fly found in Northcote

A second Queensland fruit fly has been found in a surveillance trap in the Auckland suburb of Northcote.

The detection, in what is known as Zone A in Northcote, was 113 metres from the original detection there.

A significant trapping programme has been in operation on Auckland’s North Shore since the detection of a single male Queensland fruit fly in Devonport on February 14.

All traps on the North Shore have been checked. Those traps in Zone A are checked daily for the first seven days after the find. Continue reading

Fruit fly in Auckland – situation update from MPI

A second Facialis fruit fly has been found in a surveillance trap in the Auckland suburb of Ōtara, just 70 metres from the first detection earlier in the week.

The detection of a solitary male fly within the controlled Zone A gives us confidence our trapping programme is working, says Biosecurity New Zealand spokesperson, Dr Catherine Duthie.

“We remain of the view that it is highly unlikely that a breeding population of Facialis fruit fly would establish in New Zealand because of our climate. Facialis has never established anywhere in the world outside of Tonga.

“However, our enhanced surveillance programme in the area will continue as a precautionary measure.” Continue reading

Queensland fruit fly detected in new area on Auckland’s North Shore

Surveillance activity in Auckland will be stepped up following the discovery of a second Queensland fruit fly on the North Shore.

The solitary male fly was collected from a fruit fly trap and formally identified on February 20. It’s the second Queensland fruit fly found in the past week. The first was detected in a surveillance trap in Devonport on 14 February.

The Ministry for Primary Industries director general Ray Smith says while there have now been 2 finds, it does not mean New Zealand has an outbreak of fruit fly.
Continue reading

Queensland fruit fly in Auckland – MPI provides situation update

The Ministry for Primary Industries says a large field crew continues work in the Auckland suburb of Devonport today, focused on finding out if there is an incursion of the Queensland fruit fly in the area.  This follows the detection of a lone male fly in a surveillance trap in the area last week. Since then, no further flies have been found.

If it established here, the Queensland fruit fly could seriously harm the country’s fruit and vegetable crops and affect exports of some produce. If a population is found, work will progress to eradicate it.

Current work involves:

  • extending the network of traps
  • inspecting home gardens in the area for plants that could provide suitable habitat for fruit flies
  • taking fruit and vegetable samples for testing
  • providing information to local residents and visitors.

A legal Controlled Area is in place in Devonport, restricting the movement of certain fruit and vegetables from the area.

This is a precautionary measure to prevent the spread of any fruit flies out of the area in the event a population is there.

Response staff are also working with local retailers to explain the detail of the movement controls and how they may impact their businesses. Local retailers are eligible to apply for compensation for verifiable losses incurred as a result of the legal directions.

People in Devonport who believe they have seen fruit flies or have found insect eggs or larvae inside fruit or vegetables are urged to contact the response team on 0800 80 99 66.

The press statement includes information about the insect and photos

The fruit fly response at a glance

  • More than 60 people are working in Auckland and this number continues to grow. Around 20 Biosecurity New Zealand staff are working from National headquarters in Wellington.
  • Biosecurity New Zealand’s bio-secure mobile field laboratory is established at the Devonport Naval Base.
  • Staff there are inspecting produce collected from the area for signs of fruit fly and larvae.
  • Detailed information about the fruit and vegetable controls is being distributed in the area.
  • Signs are up on key arterial roads and at the Devonport Ferry Terminal.
  • Bins are going into the Controlled Area for local people to safely dispose of fruit and vegetable waste.
  • The website address for more information is www.biosecurity.govt.nz/fruitfly

Source:  Ministry for Primary Industries

Discovery of Auckland fruit fly is under investigation

Biosecurity New Zealand is investigating a find of a single male Queensland fruit fly in a surveillance trap in the Auckland suburb of Devonport.

The fly was collected from a fruit fly trap and formally identified on the afternoon of 14 February.

Biosecurity New Zealand spokesperson Dr Catherine Duthie says the find does not mean New Zealand has an outbreak of fruit fly.

The Queensland fruit fly has been detected six times before in northern New Zealand – in Whangarei and in Auckland. Only one of  those detections, in Auckland in 2015, turned out to be a part of a wider breeding population and this was successfully eradicated by Biosecurity New Zealand. Continue reading

Queensland fruit fly count is up to eight

An eighth fruit fly has been found in Auckland, but the Ministry of Primary Industries (MPI) say it remains confident the outbreak can be contained, according to this report at Stuff. 

MPI have found three more Queensland fruit flies in Auckland over the past two days, all of them caught in traps, the report says.

More larvae have also been uncovered in fruit inside the Auckland containment zone but the Ministry said this was not a “game changer”.

All of the flies captured thus far were genetically similar, suggesting there was only one “incursion”.

“MPI remains confident it is dealing with a localised population of fruit fly that can be eradicated.”

A containment zone remains in place around the suburb of Grey Lynn, with people encouraged not to move fresh produce in and out of the area.

This could provide particularly challenging with tomorrow’s big cricket game at Eden Park, and the ministry is urging people not to take fresh fruit to the game. 58 MPI staff will attend the game, checking for fruit and removing about 10 tonnes of rubbish afterwards to minimise the risk.

The report explains that Queensland fruit flies have the potential to cause millions of dollars of damage to the New Zealand fruit industry, reducing the quality of fruit, the price exported fruit commands and potentially leading to great trade barriers for exporters.

Another Stuff report addresses the question: Why are we so afraid of the fruit fly?

The Science Media Centre earlier in the week collected expert commentary on the incursion and its containment. The expert observations can be found here.

How Govt policy is threatening NZ’s biosecurity – and its primary exports

This post has been contributed by JOHN LANCASHIRE, a former President of the NZ Institute of Agricultural and Horticultural Science –

It’s “unbelievable and unexpected” was the comment made by Peter Silcock , Horticulture New Zealand’s CEO, on hearing of the third detection of fruit fly in this country in less than two years.

Prior to these most recent occurrences it had been 16 years since the last known incursion.

It may well be unbelievable considering the huge amount of resource being put into biosecurity and the prevention of pest and weed incursions, but unexpected, certainly not. Most of our many serious pest incursions come from Australia, either carried by humans or occasionally blown over. The former comes via formal tourist and visitor routes, typically through airports or informal arrivals via private yachts which have been suggested as a possible source of the recent fruit fly incursion near Whangarei. Indeed, the present massive epidemic of Queensland fruit fly in Australia made such an incursion almost inevitable.

Continue reading